(1) Field of the Invention
The present invention relates to a processing method for a silver halide color photographic material, in particular to a processing method which makes it possible to substantially reduce the amount of waste liquor and, in turn, the pollution of the environment. In addition, the invention also pertains to a processing method which permits a saving in running cost.
(2) Prior Art
Various kinds of processing solutions have been formulated for processing silver halide color photographic materials, and the processing solution has continuously or periodically been supplemented with replenishing solution during processing, while the overflow thereof has been recovered or discarded. However, in recent years the environment has been disrupted by an increase in effluent industrial waste liquors and the like and therefore, it is desirable to minimize the amount of waste liquor from the viewpoint of environmental protection. For this reason, various processing methods have been investigated. The most general of such methods comprises reducing the amount of processing solution to be supplemented, which is also economically advantageous. Studies have been made regarding the application of this method to a variety of processing solutions such as color developers, bleaching solutions, fixing solutions and bleaching-fixing solutions and it has already been put into practical use. Moreover, other processing methods have also been proposed and disclosed in, for instance, Japanese Patent Un-examined Publication Nos. 57-8543; 57-132146; 58-18631 and 59-184343 wherein even the amount of washing water is substantially saved.
The color developer, among others, has an extremely high biological oxygen demand (BOD.sub.5) and chemical oxygen demand (COD), which are considered to be a measure of the degree of environmental pollution, and further has a buffering effect at a high pH region. Therefore, such color developer used cannot be discarded without treatment and there is no merit in recovering the used color developer, since it does not contain any valuable material such as silver. On the contrary, various studies have been conducted regarding recycling the used color developer, since the color developer per se is quite expensive and there have been proposed, for instance, a method utilizing the electrodialysis technique as is disclosed in Japanese Patent Un-examined Publication Nos. 53-7234; 53-37015; 53-149331; 54-19741 and 54-37731; a method using an ion exchange resin as is disclosed in Japanese Patent Un-examined Publication Nos. 52-146236; 53-50737 and 53-96831; West German Patent No. 2,717,674 and the like. According to these methods, it becomes possible to reduce the amount of color developers discharged to some degree. However, these methods require the use of an expensive apparatus and considerable expertise for the maintenance thereof. Such being the case, these methods have been adopted only in a few major laboratories, while in most laboratories the recycling of the color developer has not yet been carried out.